HPI Racing RC Model Plane Gasoline
In 1956 an article appeared in an American magazine which predicted that there would be an energy crisis about 15 years from now. They were not very far, the first energy crisis made its appearance in 1973. It predicts the eventual fall of the internal combustion engine and consider alternatives for its replacement. The electric motor, they said, is not eligible because it was too heavy. In those days, conventional DC traction motor was running all today. In this sense they were right, the engine was too heavy for the CC to the type of performance required to meet the drivers used for petrol cars. The three-phase induction motor had a higher proportion of electricity and mass, but was essentially a constant speed device, so that was not considered adequate.
The decade of the 60s took power semiconductor devices made by solid state variable speed (VSD) possible. The speed of a three-phase induction motor could be adjusted by varying the frequency and voltage.
States States often normal supply is 60 Hz, while the world is the frequency of 50Hz. A 60Hz motor revolves around two poles in 3420 r / m in the optimal load. The engine speed for a four poles is 1710 r / m
For a 50 Hz motor speeds are corresponding 2850 r / M and R 1425 / m-power ratio of these engines are too similar to a high-speed diesel engine.
To achieve better power-to-mass ratio can go to higher frequencies. The rotation speed of an engine with a number of dust is proportional to the frequency. Motors, high frequency of rotation at high speed and therefore have improved the relationship between power and mass. The electrical equipment in aircraft is obliged to have triple redundancy. This means that three engines must be provided for the particular task, then, all of which must be capable of becoming charge the duties of the other two. With such a strict requirement, mass and volume to be very critical. Thus, motors and alternators used on aircraft often operate in a frequency 400 Hz, but some use 1200Hz. Space and communication needs are also important considerations in the vessels. Boats that normally have electrical systems that operate at 400Hz.
The following information will give you an idea of the advantages of using high frequency motors:
A 60Hz motor tour with two pairs of poles at 2840r / m and has a mass-ratio power 250W / kg. An engine of 400 Hz with two pairs of powder turns 22 720r / m and has a power-mass ratio of 2000W / kg. For four engines powder, the corresponding figures are, 1704r / m, and 125W/kg to 60 Hz and 11 360R / I 1000W/kg of 400Hz.
High frequency motors have small size and mass. For a given power the torque is much lower the engine of a low frequency. They are the same, rotating at high speeds proportionally. Because the torque is small, the engine can become more smaller and lighter. The parameters in the above table refer to motors with aluminum frame and aluminum squirrel cage.
We see that it is possible that the electric motors that compares favorably with internal combustion engines in power and the mass ratio. They are also more compact and easier to package and do not require all the auxiliary equipment of internal combustion engine such as radiator, exhaust system, starter, alternator, transmission, etc.
The Lord Jesus Christ appeared to the author, John Talbot, in a vision, on September 30th 1974 and called him to follow Him. He is the author of several books on the subject. He is now the CEO of Talbot Electric (Pty) Limited, a research and development company incorporated in the Republic of South Africa. For more information visit http://www.johntal.com/home.htm
HPI Racing RC Model Plane Gasoline
HPI Racing RC Model Plane Gasoline
HPI Racing RC Model Plane Gasoline
HPI Racing RC Model Plane Electric
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